The concept of presence has increasingly come to the foreground of networking applications and real-time communications. Presence often refers to the ability to detect whether a user is online and available. One example of an application that takes advantage of presence information is an Instant Messenger (IM) program. An IM program provides a method for a user to send instant messages to other IM users on the Internet or on a network. IM is a type of communications service that enables a user to create a kind of private chat room with another individual in order to communicate in real time over the Internet. IM is analogous to a telephone conversation, but uses text-based, not voice-based, communication. Typically, the instant messaging system alerts a user whenever somebody on the user's private list is online. The user may then initiate a chat session with that particular individual.
However, presence for IM and other similar applications has been limited to presence information that is directly associated with a contact already established by the user. Presence of other users outside of the user's listed contacts has been unobtainable. Other applications have allowed for discovery of what devices are on a network, but not of the users.